Nomad Planets: Stepping Stones To Interstellar Space? 244
An anonymous reader writes "Ian O'Neill suggests in an opinion piece at Al Jazeera that brown dwarves and nomad planets (planets not orbiting any star) could be a much needed stepping stone on our way to foreign stars. Quoting the article: 'In February, a fascinating paper was published in the Monthly Notices of the Royal Astronomical Society detailing calculations on how many "nomad planets" the Milky Way must contain after estimating our galaxy's mass from how much gravity it exerts on surrounding space. Scientists from the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) had uncovered something surprising — there are likely many more planets in the Milky Way than stars. ... Louis Strigari and his Kavli team calculated that there must be 100,000 planets for every star in the Milky Way (PDF). That's a lot of planets! But how can this be? Every star can't have tens of thousands of planets ranging from Pluto-sized to Jupiter-sized. This planetary "excess" actually suggests the existence of planets that were born without a star — nomad planets. ... we need all the help we can get if we are to venture to another star, so these ultracool brown dwarfs could become much-needed "stepping stones" for future starships to refuel on their light-years of journey time. There may be the possibility that these sub-stellar objects may even become more desirable targets for interstellar travellers. After all, there may be dozens of these invisible objects between here and Proxima just waiting to be uncovered by the sophisticated infrared telescopes of the future; they'd certainly make for more accessible scientific curiosities.'"
Dark matter? (Score:4, Interesting)
Sounds like they're hypothesising that all the "dark matter" is actually made of planets, or did i miss something...
Also - frist prost!!!
Surprising? (Score:2)
Scientists from the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC) had uncovered something surprising — there are likely many more planets in the Milky Way than stars.
Why is that surprising? Our own solar system contains at least 8 times more planets than stars.
Re:Surprising? (Score:4, Interesting)
Re:Surprising? (Score:5, Informative)
Nomad Planets = Space Vehicles for Aliens? (Score:3)
If human of Planet Earth can think of nomad planets being vehicles to cruise the universe, you think sentient aliens from other planets wouldn't think of he same thing?
Perhaps they already are doing that
Re:Nomad Planets = Space Vehicles for Aliens? (Score:5, Insightful)
If human of Planet Earth can think of nomad planets being vehicles to cruise the universe, you think sentient aliens from other planets wouldn't think of he same thing?
Perhaps they already are doing that
As I see it, there are a couple of big problems with nomad planets. Available energy is hard to use. The environment would probably be very close to 4K (the temperature of the cosmic microwave background). I guess that there would probably be some sort of fusion, fission, or gravitational resources available for many of these places. But I doubt much energy will be available without serious technology.
Alternately, you might have life adapted to this environment with extremely slow metabolism (here, I include Earth nonlife examples such as electronics/integrated circuit systems and clockwork mechanisms). Such adaption has a price. The beam of a flashlight or the warmth of a human body even through an insulated suit might be lethal to them.
But over a long enough time, there's probably a nomad planet traveling close to you at a decent rate of speed and traveling in a direction you want to go.
Re:Nomad Planets = Space Vehicles for Aliens? (Score:4, Funny)
We must stop the bug meteors!
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Option 1. Accelerate half the way there at 9.81 m/s/s, then turn around and decelerate at 9.81 m/s/s.
Option 2. Travel at a constant speed, but spin the craft about it's axis such that the outside shell of the craft has centripetal acceleration of 9.81 m/s/s. Live on the inside using the craft's wall as a floor.
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Option 2. Travel at a constant speed, but spin the craft about it's axis such that the outside shell of the craft has centripetal acceleration of 9.81 m/s/s. Live on the inside using the craft's wall as a floor.
I've always thought this is something we should consider building now, maybe firstly as part of the ISS. The radius of the rotational shell would need to be big enough to alleviate the difference in 'gravity' a human would feel at their head and feet but that should be doable. Sure, it would still be quite an engineering feat to make it, but so is the present ISS.
Doesn't need to be as grand as the one Discovery One has in 2001: A Space Odyssey. A circular corridor with a radius of ~230m, rotating at 2rpm
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Too bad anyone attempting to reach them would go blind given the time it would take to traverse the distance and the rate at which human eyeballs deform in space.
I don't get it. Due to excessive masturbation?
Re:Too Bad (Score:5, Informative)
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Seem too low. The solar system contains only 8.2 planets. Why are so many planets in such a small volume of space?
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a small volume of space?
Space is big. Really big...
No, baryonic matter (Score:5, Insightful)
Sounds like they're hypothesising that all the "dark matter" is actually made of planets, or did i miss something...
DM cannot be made of planets because it cannot be made of atoms (it was not part of the plasma which filled the universe ~380k years after the Big Bang) nor does it have the same distribution as matter in a galaxy (rather than a disc it forms a spherical halo). The "gravitational effect" the summary misleading refers to is not the gravitational field of the galaxy but the local gravitational field of the object which bends light creating a lens effect. If the object passes between us and a distant star then the field will bend more light towards us causing the star to get brighter which is how you can detect them without seeing them.
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The summary indeed strongly suggests that these planets form (part of) the missing dark matter. So let's take that idea and run with it.
Iirc, dark matter is thought to contribute something like 80% of the total mass in our universe - several times the mass of visible matter. Without looking up the actual masses I am quite certain that the mass of the sun is several orders of magnitude larger than the mass of the planets and asteroids in our solar system together. So based on just our solar system's composit
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So the chance of meeting one of those unbound planets should be pretty high.
It takes 80 years for Haley's comet to traverse our solar system, and that's a distance of light-minutes. The nearest stars are light-years out.
We found Pluto because it caused a wobble in Neptune's orbit... unless a planet was actually in our solar system we're not going to get any clues as to its existence.
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Nearest stars are light years out indeed. The nearest is something like four light years away.
Assume there are 100,000 planets for our Sun, assume those to be in a four-light-year-radius sphere around us - volume some 270 cubic light years - there are about 400 planets in every cubic light year.
That's when they're evenly distributed, with the Sun's gravity distorting anything. So near to us there will be a much higher concentration of those hypothetical nomadic planets nearer to the Sun.
Halley's comet reach
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Turns out a cubic light year is, well, mind-bogglingly big. I wondered how an average density of 400/ly would compare with the density in our solar system.
Mind... blown.
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The orbits of planets would not be constrained by the galactic plane.
Unless you have a spherical halo of Dark Matter which is what I understand you need to stabilize spiral galaxies otherwise they rapidly (on galactic timescales) turn into elliptical galaxies....at least according to an astrophysics talk I heard a couple of weeks ago.
Re:Dark matter? (Score:5, Informative)
You missed the fact that the total mass of all these little objects is negligible compared to the amount of dark matter that needs to be accounted for. You also missed the fact that "Maybe it's all cold baryonic matter!" was the first thing the physicists thought of but when they went through the calculations they could not make the numbers work out.
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My understanding that MACHO (ie: brown dwarf and small planet) object dark matter has been pretty much ruled out by microlensing experiments. See http://en.wikipedia.org/wiki/MACHO [wikipedia.org]. Essentially if you stare at a distant star for long enough, you should see lots of gravitational microlensing (peaks in brightness) as all the small planets pass in front of the star.
Any hypothesised large amounts of dark matter would have to be fine tuned carefully to get around this data.
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No, they are not. There are nucleosynthesis limits [caltech.edu] that show that baryonic matter (us, stars, planets) are only a small fraction of the total dark matter (somewhere in the 4 to 10% range).
Now, there also is "missing" baryonic matter (about a 50% difference between what we can see and what nucleosynthesis indicates), so it must be part or even all of that. Note that stars etc are only about 10% of the baryonic matter, so I would be surprised if the planets were more than another 5% or 10% to that total, and
I'm not normally this racist, I swear. (Score:5, Funny)
Al Jazeera that brown dwarves and nomad planets
I see what you did there.
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Sometimes I wish there was a "+1, Troll" option.
light-years of journey time?? (Score:4, Informative)
When did a light year become a unit of time?
Re:light-years of journey time?? (Score:4, Informative)
When did a light year become a unit of time?
Ever since the Millenium Falcon made the Kessel Run in under 12 parsecs.
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Han was lying.
http://starwars.wikia.com/wiki/Kessel_Run
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The Kessel run was 16 parsecs through real space, was it? Uh huh.
Re:light-years of journey time?? (Score:4, Funny)
It's a route optimization problem, sort of like traveling salesman. Getting the route done in less than 12 parsecs is really good.
You want to stop at this dwarf star? (Score:5, Insightful)
Re:You want to stop at this dwarf star? (Score:5, Insightful)
Yeah, I can't really think of how this would make sense either. You really shouldn't need a lot of fuel when you're in interstellar space, because you've already expended your fuel to build up velocity; you'll just need to keep half your fuel to slow down during the second half of the voyage. These aren't ocean ships here; there's little to no resistance in space, so your ship will continue at the same velocity until you start decelerating. Maybe they're worried about running out of supplies for the people on board (like with a generation ship), but betting your survival on some random brown dwarf or starless planet along the way having usable supplies (like water, oxygen, things to convert to food) seems rather idiotic; instead, you better have the technology for near-100% recycling of all the things humans need to survive, or not bother making the trip.
And who ever said "decelerating" isn't correct any more? The same person who thinks light-year is a unit of time?
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You really shouldn't need a lot of fuel when you're in interstellar space
You might need fuel to keep the passengers alive, and that is assuming that we even develop a power system that can provide power long enough to even reach such a planet.
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Life support systems do not imply a genera
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This could be a new meme. Just fill in the blank
speed bumps (Score:3)
<pedantry>In relativistic terms, what we call "deceleration" is simply "acceleration" with the opposite vector (i.e. the other direction).</pedantry>
It's absurd to say it's an "incorrect" term, though; we are allowed to have words for opposites, after all.
But yeah: stopping at a brown dwarf or other nomad planet on an interstellar journey makes even less sense than pulling off the expressway and stopping at a gas station to walk around, when you were going 80mph and had a full tank of fuel (i.e.
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In relativistic terms, what we call "deceleration" is simply "acceleration" with the opposite vector (i.e. the other direction).
It's absurd to say it's an "incorrect" term, though; we are allowed to have words for opposites, after all.
It seems to me that it's actually a more useful term. "Acceleration" just means you're accelerating; you have to use extra words to specify more information such as the direction. With "deceleration", you're combining the fact that you're accelerating, and the direction (the
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Well, you could use them as slingshot accelerators, much as current interplanetary missions use the solar system's planets.
Which gives the slightly ridiculous possibility of interstellar travel being something like a vast game of snooker, slinging your craft around a few hundred nomad planets to build up speed then using a few hundred more to decelerate as you get close to your destination.
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That's what I was talking about, using it for gravity assist.
And your snooker game is pretty much exactly how interplanetary probes get where they're going within the solar system.
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Well, you could just walk around there for one generation or 50, while the newly aquired fuel lasts. Then you are nearer another star, and move.
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Accelerating and decelerating on an interstellar trip using only fuel you start with suffers from an exponential growth of fuel vs velocity. Look up the "Rocket Equation". If you send resupply robots ahead of the main ship, who mine these nomad objects and place fuel pellets or fuel tanks in your path so you can pick them up as you go, that turns an exponential fuel problem into a linear one. Yes, it takes work to accelerate fuel pellets, but less work than accelerating an entire ship with all it's cargo
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If you find a planet traveling in the same direction and velocity you are traveling in, as you are going in you could land without needing much fuel to stop. Refuel on the planet, then take off again. You'll now be traveling twice as fast.
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Sounds good, but it seems like the chances of finding a planet traveling in the right direction and speed are pretty slim.
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If the planet is travelling at more than the escape speed from the galaxy, it won't be in the galaxy any more. If it travelling at less than this escape speed and your ship is travelling at the same speed, you're taking at least a couple of thousand years to get to the nearest star. (And this is all before considering the chances of finding such a fortuitously placed planet.)
(Orbital speed of the sun around galactic center = approx 220 km/s, on approx circular orbit. Escape velocity = sqrt(2)*circular orbit
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If you want the trip take less than a few lifetimes you wants lots of fuel, ideally enough to accelerate at 1g the whole way. That's a lot of fuel even if it is anti-matter.
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How bout sending an unmanned daughter ship to rapidly slow down (high G forces), look around, pick up some needed minerals, and then rapidly speed up to catch the mothership? Granted, this might not make sense given today's technology, but maybe with ramscoops / fusion / who knows what rockets, this could work?
You have to think outside the spaceship.
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Actually my ship will have a force-field extending out half a light year ahead, which is incorporated into the mass-convertor. We won't need to slow down at all to pick a planet up for fuel. I heard some ethecists mention the need to stop and check for life forms but I'm not sure if they were going to be on board for the first trip.
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This was my thought too. If you're going to reach the alpha Centauri system in under a thousand years, you need to be going faster than 1200 km/s. How do they propose to refuel from something they're passing at 1200 km/s? The alternative -- expending fuel to slow down, refuel, then expend fuel to get back to speed -- is more than a little self defeating.
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Slingshots are fine pottering around the solar system, where your ship speeds are comparable to your planet escape velocities. When you're travelling at over 1000 km/s, slingshotting past a 20km/s escape velocity planet does stuff-all for you.
Gravitational anomaly (Score:3)
Galaxies having a gravity apparently bigger than their visible mass is not news, but that this effect is caused entirely by planets is unlikely. The extraordinary numbers they got are not "surprising results", but rather proof that their initial assumption was wrong. There ratio of heavy elements is too low for that many planets to form.
Freeman Dyson territory (Score:3)
I don't have the essay collection on hand, but Freeman Dyson suggested something like this a long time ago. He imagined space-adapted life spreading through archipelagos of interstellar objects.
It might have been in the essay "The Greening of the Galaxy," in his collection Disturbing the Universe.
Re:Freeman Dyson territory (Score:5, Interesting)
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So what, it would hardly matter since a human arriving at even the first "stepping stone" is likely be totally blind as a result of prolonged exposure to deep space, which causes severe permanent deformation of the human eyeball and degeneration of the optic nerve. This effect begins to occur on even much shorter trips, much less one into interstellar space. Dyson is a physicist, so its not surprising he doesn't know much about space biology.
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That effect is caused by living in microgravity, not exposure to deep space. We have the technology today to build ships that do not require the crew to live in microgravity.
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This discovery is brand new; you likely read about it a day or so ago, like I did.
Yet you're judging Dyson and his ideas on that?
An excellent piece of press-release science (Score:5, Insightful)
Colonizing vs. Searching for ET Life (Score:2)
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Enough has been spent focusing on finding life outside out planet. Let's colonize space already!
We can look for life once we get there.
Worked well enough for the crew of the Nostromo...
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Even if you could overcome these effects and could reach speeds 100 times faster than is currently possible, it would take 500 years just to reach the nearest star system.
The humans will be forever locked on Earth unless FTL is possible. Exploration robots can be sent to faraway planets even without FTL, but they will be back many thousands of years after the launch. Humans will not be able or willing to take such a trip; they won't be humans anymore by the time they land.
This is similar to exploration
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"light-years of journey time"? (Score:3)
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Thanks to C, time and distance really are interchangeable.
Billions and billions (Score:2)
Does Someone Have a Planetary Warp Coil Available? (Score:2)
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Plus the delta-V to land and take off from it.
If you can match speed with the planet then you don't really need to land on it. You are already moving as fast as the planet, and in the same direction. The only benefit of bothering to land would be in order to mine it for energy and for shelter.
However what are your chances of finding convenient supplies of fissible or fusible elements on a random piece of rock? These are largely iron - which is the end of the line, not very usable for production of ener
How could you use these to refuel? (Score:5, Interesting)
Here's the best starship concept I have come up with, based upon the assumption that there are no major undiscovered principles of physics. (aka no way to cheat basic material science or travel faster than light or cheat conservation of momentum, and relativity holds)
Technology needed : with a form of nanotechnology known as "molecular manufacturing", you can produce anything of any size with control over every atomic bond. The only limits are materials and energy. You can also deconstruct any frozen object and determine it's molecular structure.
For departing Sol, use mass drivers. Either build a gigantic mass driver that can accelerate the entire starship in one go, or give the starship a mass driver that can "catch" pellets of iron fired from a smaller one you leave back at Sol.
Either way, you want to accelerate to the desired speed as rapidly as possible. This means hundreds or thousands of Gs of acceleration. The ship is mostly solid state at this point.
At 90% of the speed of the light, the ship cruises until it gets close enough to the destination star. At this point, it reconfigures the matter about the ship into a bussard ramscoop and uses this as a brake to slow down. This way, you use free floating interstellar particles as the reaction mass instead of mass carried aboard the ship. Antimatter is used as a power source, the antimatter being burned inside a power reactor inside the ship. (antimatter does not work very well as a direct source of propulsion)
The same nanotechnology used to construct the ship can also conduct perfect repairs and quickly respond to damage (given sufficient materials and energy). That way, during the many years of travel time when the ship is cruising through the space between the stars, you can repair damage from particle impacts. Also, the ship splits into dozens of pieces separated by thousands of kilometers, enough spacing so that if part of the ship collides with a large mass at 90% of the speed of light, the rest of the ship survives.
Once at the destination star and decelerated to rest relative to the star, the ship finds a small asteroid or comet near the star. It docks with it and uses the asteroid/comet as raw materials to begin expanding infrastructure. The star provides an energy source. With exponential growth, each asteroid or comet consumed increases the infrastructure (aka a swarm of various types of robots) available, allowing bigger objects to be consumed. Eventually, there would be enough equipment built to start tearing down moons for raw materials, and eventually even planets.
Once all the mass in the star system is consumed and converted into more robots, processors, etc more ships are built and sent off like seeds to more stars to continue the process.
In principle, the entire galaxy would be nothing but dyson spheres within a million years or so.
The ultimate Fermi paradox is why has this not happened yet. We are nearing the technological capability to do this. I think we will have molecular manufacturing within 100 years. Once we find a way to copy the complexity of human brains to far faster solid state circuitry, we will create super-intelligent beings who would have the ability to solve all the engineering problems within a matter of years. If the Singularity happens, then after that event this kind of expansion would be expected to start right away. Worst case scenario, within 1000 years this should start happening.
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The ultimate Fermi paradox is why has this not happened yet. We are nearing the technological capability to do this. I think we will have molecular manufacturing within 100 years. Once we find a way to copy the complexity of human brains to far faster solid state circuitry, we will create super-intelligent beings who would have the ability to solve all the engineering problems within a matter of years. If the Singularity happens, then after that event this kind of expansion would be expected to start right away. Worst case scenario, within 1000 years this should start happening.
You're assuming a hyper-intelligent being would have the same motivation to build this that you have, and no better ideas. Also, Dyson Spheres around other starts would likely block signals of their intelligence, even if those signals were detectable by our technology, or recognizable even if they were detectable. Another solution to the Fermi Paradox is found in the Outer Limits episode "Final Exam."
And none of this takes into account that we may all be a giant simulation, anyway.
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Well my assumption is that if, say, 1000 years from now, 100 separate entities have the resources to start on this kind of expansion. You know, different corporations, political entities, group minds, whatever.
Only one of them has to start it, and in another million years, the galaxy will be nothing but copies of that entity.
Basically, over the long run, if life can replicate exponentially it will do so, because the variants of life that fail or refuse to do so are quickly swept aside.
However, yes, this Fe
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"We are nearing the technological capability to do this."
BS. The molecular biology is nowhere near there and is unlikely to be for decades if not centuries, especially considering that even routine sequence alignments constitute an NP complete problem for even modestly sized proteins and nucleic acids.
In contrast, what we do currently know about space biology strongly suggests that prolonged space travel is a contraindication for human life.
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? what does that have to do with anything. Molecular manufacturing won't depend on molecular biology, for the reasons you just mentioned.
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Once all the mass in the star system is consumed and converted into more robots, processors, etc more ships are built and sent off like seeds to more stars to continue the process.
It would be a sad story for inhabitants of that star system...
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...The ultimate Fermi paradox is why has this not happened yet. ...
We could be the first civilization in our galaxy with such grand aspirations, but with so many stars and planets around the odds are very much against that. IMO a likely explanation is that what you propose is actually much harder than you think and therefore much less likely to ever happen.
There are many serious obstacles that any such project would have to overcome before even a fleet of robots of our manufacture were ever to reach the closest nomad planet. Some obstacles are close to home, such as hum
Re:How could you use these to refuel? (Score:4, Interesting)
The starship isn't a robot, it's crewed by sentient entities.
Here's the roadmap :
1. We develop molecular manufacturing. That, simply put, is a small machine that can place a single atom at a time over and over again like a 3d printer. The machine is small enough that it itself can be produced by itself. Cells do this 24/7 with far more kludgey methods than our tech will use. (vacuum chamber + low temperature + supply of pure substrate + energy supply)
2. We then develop a machine that can cut a 3d object apart to determine it's structure, produced using meolecular manufacturing technology. Sort of a gigantic array of trillions of atomic force microscopes working in parallel.
3. We cut apart preserved and frozen human brains using this machine to get a true mapping of of human mind. With exact knowledge of how the brain's particles are connected, building artificial hardware to mimic it will be practical.
4. These artificial simulations of once living persons will run at thinking speeds constrained by the hardware, which will be probably millions of times faster than slow and inefficient human cells. If YOU could think for the apparent equivalent of a million years per earth year, you could probably learn every skill any human has in the first few millenia, then ???
This is called super-intelligence. Now, it is assumed that if someone had this kind of time and intelligence, they could turn it to revising themselves, creating an even smarter version of themselves, and so on. This explosion of increasing intelligence (til you hit some limit defined by physical laws, most likely) combined with exponentially increasing machinery is called the Singularity.
Anyways, with these kinds of resources, building starships would be child's play because you in fact would have practically infinite time, energy, and materials.
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I don't understand your viewpoint, at all.
Do you think that the human mind is not a physical object that performs computations? That said computations cannot be replicated in an equivalent device?
There are numerous papers and journal articles in the literature where accurate simulations and even replacements of pieces of brain tissue in rats have been done. Unless you simply disbelieve in evolution, you must realize that the hardware in a human skull is merely more complex, not different. If the rat simu
Do microlensing surveys this? (Score:5, Interesting)
Gravitational microlensing surveys have been looking for brown dwarfs and dim stars (sufficiently low luminosity they are not visible from Earth) in the galactic halo, but not enough were found to explain the mass difference (between luminous and non luminous galactic matter) to explain the observed galactic rotation curves. Planets around such low mass stars can also be seen (and have been seen, see the results by Microlensing Observations in Astrophyics [MOA] Project and associated collaborators - disclaimer I'm a former member). Depending on how small the planets are, they also could be detected (if you get very very lucky, due to the optical alignment required between observer, missing mass, and background luminous object). Given the constraints of the proportions of baryonic matter during the primordial nucleosynthesis (Big Bang/early universe) and the observed microlensing rate brown dwarfs are unlikely to account for the dark matter (AFAIK, I've been out of the game for a while). The baryonic constraints eliminated small rocks and gas clouds etc too. (I'm no expert on the nucleosynthesis calculations, however).
It would not be unusual for someone to come up with a theory that didn't take into account the known observations. For example, during the 1990's the early gravitational microlensing surveys 'rediscovered' the fact that our Galaxy is a 'barred spiral' - something the search teams were not aware of at the start of their studies (although astronomers, a different type of scientist, did know this). So it would not be unusual for someone to be missing key observations that invalidate this 'many planet theory'. Fortunately for the microlensing surveys their observations and results lead them to the correct conclusion (barred spiral galaxy), which instilled confidence in their methods and results. It doesn't take away from the fact that what was already known by astronomers was not at the time commonly known amongst the astrophysicists/particle physicists who designed the early microlensing surveys. It wouldn't surprise me if this was also the case in the paper /theory being discussed in this thread.
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The fine article says that this result is extrapolated from microlensing survey results.
I have a peripheral connection with MOA myself. Phil Yock was my MSc cosupervisor (pre-MOA) and later I travelled to the telescope and helped with some setup, mostly of the computers. I also told them that I didn't think using "sleep 30" to control the exposure time was a good idea.
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Fortunately things have changed with regard to acquisition.
And the baryonic composition of the dark matter?
How to find nomad planets? (Score:2)
Interesting idea (not sure it's necessarily a *good* idea, but nevertheless worth consideration), but there's one issue I can foresee:
How do you *find* the things?
Planets don't emit light. They don't really do much of anything to draw our attention. It can be difficult to spot planets even in our own solar system - Neptune, far from the smallest planet, is invisible to the naked eye, and Pluto (a dwarf planet, I know) is extremely tricky for the amateur astronomer to observe due to its distance and, more im
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You put a giant telescope on space, and use gravity lensing to detect them.
Probably better done with a RF telescope.
Is there an astrophysicist in the house? (Score:2)
I was taught in school, and thus assume to be the gospel truth, that planets are formed by a spinning disk of excess matter being thrown off by a young star. So where do nomad planets come from? And are they actually solid, or just mini-gas giants? After all, the galaxy is composed primarily of gas, with all the higher numbered elements being created exclusively within stars, right?
I'm having trouble seeing how these planets could form at all, let alone be so ubiquitous.
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Those spinning disks may not be dense enough to ignite into a star, but dense enough to form these plants that wind up "going rogue", is my understanding. I could be wrong. Or maybe the stars were destroyed in a war. You never know.
Sterrrriliiiiiiize! (Score:2)
You've made a mistake! (Score:2)
You are imperfect! You know what you must do.
that would be like (Score:2)
Why not... (Score:3)
Been there done that (Score:2)
it's called Fleet of Worlds
after a while technical civilizations start noticing that a star is more of a liability than an asset, so they just... get rid of the star.
Nomad Building (Score:2)
With all the resources that only a civilisation like Magrathea might have, we could build our own Rama cylinder! w00t!
Step One: Find a big chunk of floating planet.
Step Two: Reconfigure the resources
Step Three: ???
Step Four: Profit
Step Five: Let your next generation prodigy meet the humans who got to whichever star or another in two weeks.
Step Six: What? You're probably dead now anyhow. Great time to be a joke.
Step Seven: This step intentionally left blank.
no stepping stone for you (Score:2)
Re: Best Known Ways (Score:3)
I'm writing a book on that subject. There are way more than gravity slingshots. That's #73 out of 83 on the list so far, and I'm only 1/3 of the way to a first draft:
http://en.wikibooks.org/wiki/Space_Transport_and_Engineering_Methods [wikibooks.org]
Stepping stones? (Score:2)
"What do you think, Helena?"
"Oh John, those poor aliens need our help!"
"So be it. Victor, can you reprogram Computer to land this planet on a planet?"
"Oh I don't know, John. Maybe we should go down in an Eagle instead?"
"Good thinking. Alan, lift-off in 5 minutes!"
Makes me... (Score:2)
want to play "Spaceward Ho!"
Re: (Score:2)
I see it more as:
1. robot ships carrying seeds and frozen embryos to be developed when a suitable planet is found.
2. or life evolves to a mechanical form that can stand space radiation, long duration voyages.
Re: (Score:2)
Re: (Score:2)
I can see it now either way you go: physical snail mail: "Sorry no one by this name at this address". Or email: "Mailer daemon unable to transmit your message, please resend".
I think humanity would be far better off studying space with probes, telescopes, and robots and forget the manned travel as pure fantasy. Better to put that kind of money into exploring our oceans, which are actually far more poorly studied than outer space, particularly in terms of funding, with a far greater likely payoff for human
Re: (Score:3)
A parsec is a measure of distance not of time.
Re: (Score:2, Informative)
Wow, you are an idiot.